- Vb Net Update Progress Bar Backgroundworker Thread Up Online
- Vb Net Update Progress Bar Backgroundworker Thread Up Official Site
- Progress Bar W3schools
- Vb.net Update Progress Bar
It is up to the developer to use the correct functionality ie methods, and properties to ensure the background worker reports its progress with BackgroundWorker.ReportProgress which raises the BackgroundWorker.ProgressChanged Event which is used for updating the user as progress commences and runs its cycle, and said developer should also. A simple demonstration of how to use a BackgroundWorker with a ProgressBar. 13,832,357 members. (100); // Back on the 'UI' thread so we can update the progress bar void backgroundWorker1ProgressChanged(object sender. VB.Net Code for BackgroundWorker and ProgressBar Demo. Member 8863655 16-May-13 11:34. It is up to you to implement a meaningful way of measuring your background operation's progress as a percentage of the total task completed. The call to the ReportProgress method is asynchronous and returns immediately. The ProgressChanged event handler executes on the thread that created the BackgroundWorker.
Updating a progress bar
Updating a progress bar
I've searched everywhere for an answer to my problem. Everything I have found refers to something totally different than what I'm trying to do. I'm going to try writing up my problem here and maybe someone can give me a good solution.1. I have a windows application with many winform objects to handle printing each with a progress bar and label on it. The winform is written in vb.net. My desktop application, which is written in vb.net, has many forms that generate reports. They all have the same basic premise of having report criteria controls as well as a progress bar and label.
2. I create a report that calls a method in a dll. The dll uses the PrintDocument class to create the actual report. That code is written in C#.
3. I have a special class that is located in the printing dll that is accessible from the desktop application. Among the things in that class are places for the progressbar and label.
4. During the printing of the report, I update the progress bar once per each loop through the data set.
The problem is I can't make the changes of the progressbar update to be seen in real time. It seems that the only time it does visually change is if I have to leave the print handler as I go from page to page. That tells me that this code isn't processing in real time. In fact, if I set a breakpoint right at the end of the updateProgressBar() and run the app, the progressbar does update. Of course, I have to keep hitting F5 to advance. So I need to find a way to make it happen during the print loop. I believe that is where the backgroundworker stuff comes in. However, I have no idea how to make that kind of code, so could use some serious help.
Here are some code snippets:
oPD = new xxxPRINTING.pdCommon(); // special object that contains many printing parameters and functions..
// including:
public void updateProgressBar ( ProgressBar pBar, System.Windows.Forms.Label lblCaption, int numRecs, int numCurrentRec )
{
if ( pBar != null )
{
// pBar.Increment (1);
pBar.PerformStep ();
pBar.Update (); // things to do to try to force the updated progressbar show..
pBar.Refresh ();
if ( lblCaption != null ) lblCaption.Text = String.Format ( 'Printing record {0} of {1}', numCurrentRec.ToString(), numRecs.ToString() );
System.Windows.Forms.Application.DoEvents();
} // <--- if I set a breakpoint here, then the progressbar updates with show. If I don't break here, the displayed progressbar is haphazard at best.
}
Print handler setup:
pD.PrintPage += new PrintPageEventHandler ( pDPrintReport );
pD.Print();
pD.PrintPage -= new PrintPageEventHandler ( pDPrintReport );
Printing loop. This code is found in the print event handler 'pDPrintReport' setup above:
for ( ; currentMember < numRecs; currentMember++ )
{
oPD.updateProgressBar ( localPrinterSettings.pBar, localPrinterSettings.lblCaption, numRecs, currentMember + 1 );
.
.
Vb Net Update Progress Bar Backgroundworker Thread Up Online
Vb Net Update Progress Bar Backgroundworker Thread Up Official Site
.yPos += oPD.lineHeight;
if (yPos >= BottomOfPage)
break;
}
// When I get here, it means that x number of records have peen printed and the veretical position has gone base the logical end-of-page.
// The progressbar DOES update when I get here..
if (currentMember >= numRecs )
{
e.HasMorePages = false;
}
else{
currentMember++;
Progress Bar W3schools
}
Vb.net Update Progress Bar
Thanks in advance,Jerry
Jerry Scannell
The progress bar is one of those universal objects that everyone recognizes, it’s useful when doing a large or long task. For example, if your updating/deleting/copying a bunch of files you can update the progress bar as you modify each file.
There are several lines of code to pay attention to, let me outline them here in further detail.
Line 7 – we can think of the maximum as how many steps their are. We can say we want a 1000 steps, or only 20 steps. This makes it useful if you want to update a random number of objects stored in an array, in that case we could store the ProgressBar1.Maximum = UBound(arrSomeArray).
Line 9 – we are just initializing our progress bar to 0
Line 11 – we make the progress bar visible. This step is up to you, I infrequently use the progress bar and I usually keep it hidden until I have a reason to display it. If your progress bar is already visible you can delete this line of code
Line 13 – this line is completely unrelated to the progress bar, whatever value is specified in the Sleep argument is how long your application will wait to update. In this application, I decided to wait 1000 milliseconds (or 1 second) before I goto the next step, this will allow us to see the progress bar update so we can simulate a test scenario.
Line 15-29 Buds brp keygen. – This is just updating the progress bar, then waiting some more, nothing to special going on here. As you can see the value I am raising the progress bar is completely arbitrary.
Line 30 – Print out a message box saying complete
Line 31 – Hide the progress bar so that it is no longer visible, we’ve already told the user that the task is complete, there’s no need to continue showing the progress bar. Again, this line of code is entirely up to you.
This is the code for a VB.NET progress bar example
This is the source code for a C# progress bar example
The code only varies slightly in C#, I’ll make sure to explain any differences. Besides the semicolons at the end of every line, only lines 12, 31, and 32 differ from the VB.NET example.
Line 12, Line 32 – Boolean values must be in lower case.
Line 31 – Showing a message box is slightly different in VB.NET, if you didn’t add the following headers using System.Windows.Forms; Reliable iphone unlock service. in your source code, then you will need to specify the full class name. I included it so that this example can work on as many peoples projects as possible. If you are already including Systems.Windows.Forms then you can show a message box by replacing line 31 with: MessageBox.Show(“Complete!”);